Four flavors of time-discounting I endorse, and one I do not

(I apologize in advance for a bit of a long post. There is a more concise summary at the end.)

We often choose between doing good for the people of today and doing good for the people of the future, and are thus faced with a question: how do we trade off good now vs. good later? A standard answer to this question is to invoke exponential time discounting with one discount rate or another.

When I consult my intuition, I find that at least over the next few thousand years, I don’t much care about whether someone gets happier today or happier tomorrow—it’s all the same to me. (See also here for a much more thorough and correct discussion of this issue, and see here¬†for a much more poetic description.)

Nevertheless, there are a few senses in which I do discount the future, and I think it’s important to bring those up to clarify what I do (and don’t mean) by saying that I have weak time preferences. Read the rest of this entry »